Battery life statistics...

Newsweek brings us the truth behind battery life claims. We all know that we never get the manufacturer's claim but now I finally understand why. As Newsweek brings it: "Imagine if automakers got together and started measuring the gas mileage of new cars with a cool test of their own making--one in which the cars were rolling downhill with their engines idling. Suddenly you'd have some pretty amazing claims: Why, that three-ton SUV gets 300 miles per gallon! This subcompact gets 500! In tiny print at the bottom of the window sticker you'd find a disclaimer saying that, well, um, you know, your mileage may vary."

This is because battery-life numbers are based on a benchmark test called MobileMark 2007 (MM07). The test was created by a consortium called BAPCo (Business Application Performance Corp.), whose members are--you guessed it--computer makers and other tech companies. Laptops score big numbers because they're tested with screens dimmed to 20 to 30 percent of full brightness, the Wi-Fi turned off and the main processor chip running at 7.5 percent of capacity--just like those cars idling downhill.

But there is some light at the end of the tunnel. There is discussion on a new benchmark, which would state Active Time and Resting Time. A bit like mobile phones do with talking time and standby-time. AMD is promoting this and some laptop makers are seriously considering it. And they better do, because the alternatives are government interruption or a class-action lawsuit..." For now, count 50% of the battery time the manufacturers claim and you have a good real-life estimate.